Custom workweeks
Choose Monday–Friday, Sunday–Thursday, Monday–Saturday, or select individual working weekdays.
ToolRelief Decision Tool · Planning & Deadlines
Business Days Calculator with Holidays & Custom Workweeks
Count working days between two dates, add or subtract business days, calculate workdays in a month or year, choose your working week, optionally exclude national public holidays, and add company-specific closure dates.
Free to use
No signup required
Custom workweek support
Optional holidays by country
Shareable calculations
Quick answer
What does a business days calculator do?
A business days calculator counts dates that match a selected working week while excluding non-working weekdays and, when enabled, public holidays and custom closure dates. It can also add or subtract a number of business days from a date to estimate a project, invoice, delivery, review, renewal, or internal planning deadline.
Between datesCount business and calendar days
Add / subtractFind a future or prior working date
Month / yearCount workdays in a selected period
Custom calendarWorkweeks, holidays, and closure dates
Calculate business days your way
Choose a calculation mode, define the working week, and decide whether public holidays or custom excluded dates should affect the result. Your calculation inputs stay in the browser; date-level holiday data is requested only when you enable public-holiday exclusion.
Public holidays (optional)
The list may expand automatically when the holiday service is available.
Holiday data is optional and loaded only when requested. Regional, state, religious, company, banking, school,
observed-day, or locally announced closures may differ. Add important dates manually and verify critical deadlines.
Custom excluded dates
More than weekend subtraction
Model the calendar you actually work.
A useful workday calculator should not assume every organization follows the same Monday–Friday calendar. ToolRelief lets the working week, public-holiday layer, and company-specific closures change the calculation.
Optional public holidays
Exclude national/global public holidays for a selected country when the holiday data service is available.
Company closure dates
Add shutdowns, team offsites, internal holidays, or other dates that should not count as working days.
Calculation methodology
How ToolRelief counts a business day
A date counts as a business day only when its weekday is selected as a working day and the date is not excluded by an enabled public-holiday calendar or a custom excluded date. A holiday that already falls on a non-working weekday is not subtracted twice.
Business days between dates
Eligible dates in the selected range − non-working weekdays − qualifying public holidays − custom excluded workdays.
Add or subtract business days
Move one calendar date at a time in the selected direction and increment the counter only when the date qualifies as a business day.
Workdays in a month or year
Evaluate every date in the selected period using the same workweek and exclusion rules.
Holiday data & limits
Public holidays are a data layer, not a universal legal calendar.
When you enable public-holiday exclusion, the calculator requests public-holiday data from the Nager.Date public API. The tool uses national/global entries for the selected country and keeps company-specific dates under your control. If the holiday request fails, ToolRelief does not silently pretend the holiday layer was applied; the result tells you that the calculation fell back to the selected workweek and custom exclusions.
National / global holidays
Used when returned by the selected country calendar.
Regional & company dates
Add them manually when they matter to your scenario.
Critical deadlines
Verify against the authoritative calendar, contract, regulator, court, or professional adviser.
Common use cases
Where business-day calculations help
The calculator is designed for practical operating and planning scenarios rather than one narrow SaaS workflow.
Project timelines
Estimate real working time between a kickoff date and a delivery or review milestone.
Invoice & payment planning
Model internal due-date windows using the workweek that applies to your business process.
Delivery & operations
Compare calendar time with actual working days available for fulfillment, review, or handoff.
Procurement & renewals
See how many working days remain before an internal purchase, vendor review, or renewal decision date.
Team scheduling
Exclude company closures, offsites, shutdowns, or custom non-working days from an operating window.
Travel operations
Estimate internal processing or planning windows around travel tasks without treating the output as an immigration or legal deadline.
Definitions
Business days, working days, and calendar days
Searchers often use “business days,” “working days,” and “workdays” interchangeably, but the calendar rules behind them can differ by organization and country.
Business day
A date your selected business calendar treats as working. In this tool, it must be a selected weekday and not an excluded holiday or custom closure.
Working day / workday
Usually another term for a business day. The exact working week can vary, so this calculator lets you define the weekdays that count.
Calendar day
Any date on the calendar, including weekends, public holidays, and other non-working dates.
Continue the decision
Use the result in the context that matters.
A working-day answer is often only the first step. Continue into the relevant ToolRelief path instead of forcing every date calculation into SaaS.
Business Calculators
Return to the broader calculator hub for cost, date, planning, software, and travel calculations.
Explore calculators →SaaS Renewal Risk Calculator
If the date is a software renewal window, evaluate renewal exposure and the next review step.
Review renewal risk →Smart Trip Planner
If the date window belongs to travel planning, continue into ToolRelief’s travel decision path.
Plan a trip →The ToolRelief System
See how ToolRelief connects calculators, evidence, comparisons, software intelligence, offers, and travel decisions.
View the system →
Common questions
Business Days Calculator FAQ
Direct answers about working days, holidays, deadlines, and calculation rules.
How do I calculate business days between two dates?
Enter the start and end dates, choose the weekdays that count as working days, and decide whether to exclude public holidays or custom closure dates. The calculator evaluates each date in the selected range and counts only dates that satisfy those rules.
How do I add 10 business days to a date?
Choose “Add / subtract workdays,” select the start date, choose “Add business days,” enter 10, then define your workweek and holiday settings. The calculator moves forward one calendar date at a time and counts only qualifying business days.
Can I subtract business days from a date?
Yes. In the add/subtract mode, change the operation to “Subtract business days.” The same selected workweek, public-holiday setting, and custom excluded dates are applied in reverse.
Does the calculator support Sunday–Thursday workweeks?
Yes. Choose the Sunday–Thursday preset or select any combination of weekdays manually. This makes the tool useful for organizations whose standard working week is not Monday through Friday.
Does this business days calculator include public holidays?
Public-holiday exclusion is optional. Select a country and enable public holidays to request national/global holiday data. Regional, company, school, banking, religious, or locally announced closures may differ, so important dates should be verified and can also be added manually.
Can I add company holidays or shutdown dates?
Yes. Use Custom excluded dates to add company closures, team offsites, internal holidays, or any other date that should not count as a business day for your calculation.
Can I calculate the number of working days in a month or year?
Yes. Choose “Workdays in month / year,” select the period, and apply the same workweek, public-holiday, and custom-date rules.
Can I use this for legal, court, tax, regulatory, or immigration deadlines?
Do not rely on this calculator as the authoritative source for legal or jurisdiction-specific deadlines. Official rules can define business days differently and may include special filing, observed-holiday, emergency, time-zone, or local-calendar rules. Verify critical deadlines with the relevant authority, contract, or qualified professional.
Planning tool, not an authoritative deadline service.
ToolRelief Business Days Calculator is designed for general planning, operations, projects, invoice timing, internal reviews, delivery estimates, and scenario testing.
Public-holiday data and custom settings may not reproduce legal, court, tax, regulatory, banking, government, contract-specific, or regional deadline rules.